The subject invention is related generally to drive shaft assemblies for internal combustion engines, turbines, armatures and the like, and is specifically directed to a power takeoff adapter for extending the drive shaft.
Typically, where power units such as internal combustion engines and the like are used in a variety of applications, each unit requires a variety of drive shafts, each specifically designed for particular applications. Since the drive shaft is a basic component of the power unit, it is part of the initial assembly. This requires that the power application be known at the time of assembly to assure installation of the power drive shaft. When power units are mass produced for a variety of applications, it is not always possible, to predetermine the end use and application. Often, this results either in the requirement that the unit be disassembled and the drive shaft changed out to accommodate specific applications or that quantities of the various types be stocked. In the first case, disassembly and reassembly is time consuming and unnecessarily adds to the manufacturing cost of the unit. In the second case, overhead costs or lack of level scheduling exists.
Known prior art devices incorporated add-on drive shaft extensions having a male threaded drive shaft stub with a female tapped extension and a driving feature such as an external hexagonal drive or other additional fastening components which were attached to the extension. The use of the female tapped extension limits the ability of the drive shaft extension device to accept internally threaded load and restricts the end use of the power unit, particularly where space and size of the extension is limited.
Examples of crankshafts adapted for receiving the female tapped extensions are shown, for example, in U.S. Pat. Nos. 4,624,156 issued to Kamata on Nov. 25, 1986; U.S. Pat. No. 1,845,110 issued to Wright on Feb. 16, 1932 and U.S. Pat. No. 1,440,685 issued to Korvin-Kroukovsky on Jan. 2, 1923.
A tapered splice for crankshaft bearings female threaded end is shown and described in U.S. Pat. No. 1,839,623 issued to waddell on Jan. 5, 1932.